Material Shows Weakening of Climate Reports

WASHINGTON, March 19 — A House committee released documents Monday that showed hundreds of instances in which a White House official who was previously an oil industry lobbyist edited government climate reports to play up uncertainty of a human role in global warming or play down evidence of such a role.

In a hearing of the House Committee on Oversight and Government Reform, the official, Philip A. Cooney, who left government in 2005, defended the changes he had made in government reports over several years. Mr. Cooney said the editing was part of the normal White House review process and reflected findings in a climate report written for President Bush by the National Academy of Sciences in 2001.

They were the first public statements on the issue by Mr. Cooney, the former chief of staff of the White House Council on Environmental Quality. Before joining the White House, he was the “climate team leader” for the American Petroleum Institute, the main industry lobby.

He was hired by Exxon Mobil after resigning in 2005 following reports on the editing in The New York Times. The White House said his resignation was not related to the disclosures.

Mr. Cooney said his past work opposing restrictions on heat-trapping gases for the oil industry had had no bearing on his actions once he joined the White House. “When I came to the White House,” he testified, “my sole loyalties were to the president and his administration.”

Mr. Cooney, who has no scientific background, said he had based his editing and recommendations on what he had seen in good faith as the “most authoritative and current views of the state of scientific knowledge.”

Mr. Cooney was defended by James L. Connaughton, chairman of the environmental council and his former boss.

The hearing was part of an investigation, begun under the committee’s Republican chairman last year, into accusations of political interference in climate science by the Bush administration. It became a heated and largely partisan tug of war over the appropriate role of scientists and political appointees in framing how the government conveys information on global warming.

The hearing also produced the first sworn statements from George C. Deutsch III, who moved in 2005 from the Bush re-election campaign to public affairs jobs at NASA. There he warned career press officers to exert more control over James E. Hansen, the top climate expert at the space agency.

Testifying at the hearing, Dr. Hansen said editing like that of Mr. Cooney and efforts to limit scientists’ access to the news media and the public amounted to censorship and muddied the public debate over a pressing environmental issue. “If public affairs offices are left under the control of political appointees,” he said, “it seems to me that inherently they become offices of propaganda.”

Republicans criticized Dr. Hansen for what they described as taking political stances, for spending increasing amounts of time on public speaking and for accepting a $250,000 Heinz Award for environmental achievement from the Heinz Family Philanthropies, run by Teresa Heinz Kerry, the wife of Senator John Kerry, Democrat of Massachusetts.

Representative Darrell Issa, Republican of California, proposed that Dr. Hansen, by complaining about efforts to present two sides on global warming research, had become an advocate for limiting the debate.

Dr. Hansen replied, “What I’m an advocate for is the scientific method.”

Mr. Deutsch said his warnings to other NASA press officials about Dr. Hansen’s statements and news media access were meant to convey a “level of frustration among my higher-ups at NASA.”

Mr. Deutsch resigned last year after it was disclosed that he had never graduated from Texas A&M University, as his résumé on file at NASA said. He has since completed work for the degree, he said Monday.

Democrats focused on fresh details that committee staff members had compiled showing how Mr. Cooney made hundreds of changes to government climate research plans and reports to Congress on climate that raised a sense of uncertainty about the science.

The documents “appear to portray a systematic White House effort to minimize the significance of climate change,” said a memorandum circulated by the Democrats under the committee chairman, Representative Henry A. Waxman of California.

A version of this article appears in print on , on page A16 of the New York edition with the headline: Material Shows Weakening Of Climate Change Reports. Order Reprints|Today's Paper|Subscribe